Table of Contents
Advertisement
Troubleshooting
9
Troubleshooting
Observe the safety instructions in Ch. Safety, from page 5 on.
Electrical faults may only be processed by a qualified electrician. Work on
Expertise and
the VSI may only be carried out by authorised persons.
regulations
In the case of unauthorised intervention in the VSI there is no longer any
warranty claim. Interventions of any kind are to be agreed upon with
ter
Malfunctions
In the case of malfunctions of the VSI proceed as follows:
and causes
Malfunction
The measured frequency
changes continuously
between two or more
values which differ con-
siderably (more than
10%) from each other.
The measured stroke
differs distinctively from
a reference value which
has been ascertained
through a different
measuring method.
The acceleration dis-
played is always zero,
although the sensor is
attached to a vibrating
system.
18
Vibration.
Possible causes
The measured vibration
is composed of two or
more harmonic vibra-
tions which contribute
nearly equally to the
overall vibration.
The sensor is not firmly
fixed to the system to be
measured or detaches
repeatedly from the
measuring surface dur-
ing the measurement.
The vibration deviates
considerably from a si-
nusoidal wave.
The sensor is not
aligned parallel to the
vibration direction.
The sensor is aligned at
a 90-degree angle to the
vibration direction.
The sensor is defective
or the measuring unit is
defective.
Corrective action
If only the lowest frequency of a
system with several excita-
tion/resonance frequencies is to
be measured, a mechanical
dampening (e. g. a rubber pad
placed below the sensor) can be
used in order to hide higher fre-
quencies during the measurement
(mechanical low pass filter).
Fasten the sensor correctly. The
sensor must be firmly attached to
the measuring surface.
The measurement of the vibration
amplitude will only be reliable if
the measured acceleration is si-
nusoidal.
The longitudinal axis of the sensor
must be aligned parallel to the
vibration direction or radially in
case of circular vibrations.
The longitudinal axis of the sensor
must be aligned parallel to the
vibration direction or radially in
case of circular vibrations.
Send the measuring unit (control-
ler) including sensor and connect-
Netter
Vibration for
ing cable to
checking and repair.
Net-
Advertisement
Table of Contents
